Dissertations / Theses: 'Vacuum technology'

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Söderman, Daniel, and Högfeldt Simon Ahlin. "Dynamically Controlled Vacuum Level for Vacuum Pad Grippers." Thesis, KTH, Maskinkonstruktion (Inst.), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-246158.

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Vacuum grippers are widely used in the industry where objects needs to be gripped and moved. There is a need to reduce the consumption of compressed air that is used to create vacuum. This project aims to investigate one method to reduce this. A system where the vacuum level is dynamically controlled is proposed to reduce the compressed air consumption during the lift. The acceleration of the object during the lift is used to calculate the vacuum level required to hold onto the object, ensuring that the vacuum level remains at its minimum value during the lift. A valve system that can control the vacuum level dynamically was designed. This consisted of a stepper motor connected to a valve, which takes readings from a vacuum sensor to form a closed loop system that controls the vacuum level. A Fanuc robot was used to do lifts on certain objects. Acceleration data was gathered from these lifts and used to calculate the necessary vacuum level. This array of vacuum values to be used during the lift was sent to the control system and an external system measured the consumed air during the lift. The comparison in air consumption was done for these dynamic vacuum values and a constant vacuum value which is set to the lowest constant value needed to hold onto the object during the lift. The testing to determine the air consumption was first done using the calculated reference vacuum but without the robot to determine how well the system performed. These comparisons showed that the reduction of compressed air consumption was between 19.5% - 29.0% when testing without the robot. A single test case was chosen for testing with the robot and the air consumption reduction in this case was 11.3%
Inom industrin används ofta vakuum tillsammans med sugkoppar för att greppa objekt som sedan kan flyttas. För att producera detta vakuum används tryckluft. Det finns ett stort intresse av att reducera användningen av tryckluften. Detta projekt har som mål att undersöka en ny metod som möjligtvis skulle kunna bidra till denna reducering. Undersökningen gäller ett system där systemets vakuumnivå ändras dynamiskt under ett lyftfall. Accelerationen av det förflyttade objektet mäts för att beräkna en vakuumnivåkurva som referens. Denna nivåkurva är den minsta möjliga för att objektet ska kunna hållas av sugkoppen under hela lyftet, baserat på kraften som accelerationen orsakar. Ett ventilsystem som dynamiskt styr vakuumnivån har utvecklats. Denna design består av en stegmotor som är kopplad till en ventil. Detta system mäter vakuumnivån som sedan används som ett closed loop system som styr vakuumnivån. En Fanuc robot användes för olika lyftfall. Accelerationsdata mättes från dessa lyftfall för att sedan beräkna den krävda vakuumnivån. Dessa vakuumvärden användes som referensdata i kontrolsystemet. Utöver detta användes ett externt mätsystem som mätte användandet av tryckluften under lyftprocessen. Jämförelser gjordes sedan mellan de dynamiska fallen jämfört med ett fall med en konstant nivå av tryckluft. Denna konstanta nivå sattes som den lägsta vakuumnivå som krävdes för att klara hela lyftet. Testen utfördes både med och utan användandet av en robot. Resultatet av dessa jämförelser visade att en minskning av tryckluftsförbrukning kunde göras mellan 19,5% - 29,0% utan roboten. Med roboten var denna minskning för ett specifikt testfall 11,3%

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Karami, Peyman. "Robust and Durable Vacuum Insulation Technology for Buildings." Doctoral thesis, KTH, Byggnadsteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176494.

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Today’s buildings are responsible for 40% of the world’s energy use and also a substantial share of the Global Warming Potential (GWP). In Sweden, about 21% of the energy use can be related to the heat losses through the climatic envelope. The “Million Program” (Swedish: Miljonprogrammet) is a common name for about one million housing units, erected between 1965 and 1974 and many of these buildings suffer from poor energy performance. An important aim of this study was to access the possibilities of using Vacuum Insulation Panels (VIPs) in buildings with emphasis on the use of VIPs for improving the thermal efficiency of the “Million Program” buildings. The VIPs have a thermal resistance of about 8-10 times better than conventional insulations and offer unique opportunities to reduce the thickness of the thermal insulation. This thesis is divided into three main subjects. The first subject aims to investigate new alternative VIP cores that may reduce the market price of VIPs. Three newly developed nanoporous silica were tested using different steady-state and transient methods. A new self-designed device, connected to a Transient Plane Source (TPS) instrument was used to determine the thermal conductivity of granular powders at different gaseous pressure combined with different mechanical loads. The conclusion was that the TPS technique is less suitable for conducting thermal conductivity measurements on low-density nanoporous silica powders. However, deviations in the results are minimal for densities above a limit at which the pure conduction becomes dominant compared to heat transfer by radiation. The second subject of this work was to propose a new and robust VIP mounting system, with minimized thermal bridges, for improving the thermal efficiency of the “Million Program” buildings. On the basis of the parametric analysis and dynamic simulations, a new VIP mounting system was proposed and evaluated through full scale measurements in a climatic chamber. The in situ measurements showed that the suggested new VIP technical solution, consisting of 20mm thick VIPs, can improve the thermal transmittance of the wall, up to a level of 56%. An improved thermal transmittance of the wall at centre-of-panel coordinate of 0.118 to 0.132 W m-2K-1 and a measured centre-of-panel thermal conductivity (λcentre-of-panel) of 7 mW m-1K-1 were reached. Furthermore, this thesis includes a new approach to measure the thermal bridge impacts due to the VIP joints and laminates, through conducting infrared thermography investigations. An effective thermal conductivity of 10.9 mW m-1K-1 was measured. The higher measured centre-of-panel and effective thermal conductivities than the published centre-of-panel thermal conductivity of 4.2 mW m-1K-1 from the VIP manufacturer, suggest that the real thermal performance of VIPs, when are mounted in construction, is comparatively worse than of the measured performance in the laboratory. An effective thermal conductivity of 10.9 mW m-1K-1 will, however, provide an excellent thermal performance to the construction. The third subject of this thesis aims to assess the environmental impacts of production and operation of VIP-insulated buildings, since there is a lack of life cycle analysis of whole buildings with vacuum panels. It was concluded that VIPs have a greater environmental impact than conventional insulation, in all categories except Ozone Depilation Potential. The VIPs have a measurable influence on the total Global Warming Potential and Primary Energy use of the buildings when both production and operation are taken into account. However, the environmental effect of using VIPs is positive when compared to the GWP of a standard building (a reduction of 6%) while the PE is increased by 20%. It was concluded that further promotion of VIPs will benefit from reduced energy use or alternative energy sources in the production of VIP cores while the use of alternative cores and recycling of VIP cores may also help reduce the environmental impact. Also, a sensitivity analysis of this study showed that the choice of VIPs has a significant effect on the environmental impacts, allowing for a reduction of the total PE of a building by 12% and the GWP can be reduced as much as 11% when considering both production and operation of 50 yes. Finally, it’s possible to conclude that the VIPs are very competitive alternative for insulating buildings from the Swedish “Million Program”. Nevertheless, further investigations require for minimizing the measurable environmental impacts that acquired in this LCA study for the VIP-insulated buildings.
Dagens byggnader ansvarar för omkring 40% av världens energianvändning och står också för en väsentlig del av utsläppen av växthusgaser. I Sverige kan ca 21 % av energianvändningen relateras till förluster genom klimatskalet. Miljonprogrammet är ett namn för omkring en miljon bostäder som byggdes mellan 1965 och 1974, och många av dessa byggnader har en dålig energiprestanda efter dagens mått. Huvudsyftet med denna studie har varit att utforska möjligheterna att använda vakuumisoleringspaneler (VIP:ar) i byggnader med viss fokus på tillämpning i Miljonprogrammets byggnader. Med en värmeledningsförmåga som är ca 8 - 10 gånger bättre än för traditionell isolering erbjuder VIP:arna unika möjligheter till förbättrad termisk prestanda med minimal isolerings tjocklek. Denna avhandling hade tre huvudsyften. Det första var att undersöka nya alternativ för kärnmaterial som bland annat kan reducera kostnaden vid produktion av VIP:ar. Tre nyutvecklade nanoporösa kiselpulver har testats med olika stationära och transienta metoder. En inom projektet utvecklad testbädd som kan anslutas till TPS instrument (Transient Plane Source sensor), har använts för att mäta värmeledningsförmågan hos kärnmaterial för VIP:ar, vid varierande gastryck och olika mekaniska laster. Slutsatsen blev att transienta metoder är mindre lämpliga för utföra mätningar av värmeledningsförmåga för nanoporösa kiselpulver låg densitet. Avvikelsen i resultaten är dock minimal för densiteter ovan en gräns då värmeledningen genom fasta material blir dominerande jämfört med värmeöverföring genom strålning. Det andra syftet har varit att föreslå ett nytt monteringssystem för VIP:ar som kan användas för att förbättra energieffektiviteten i byggnader som är typiska för Miljonprogrammet. Genom parametrisk analys och dynamiska simuleringar har vi kommit fram till ett förslag på ett nytt monteringssystem för VIP:ar som har utvärderats genom fullskaleförsök i klimatkammare. Resultaten från fullskaleförsöken visar att den nya tekniska lösningen förbättrar väggens U-värde med upp till 56 %. En förbättrad värmegenomgångskoefficienten för väggen i mitten av en VIP blev mellan 0.118 till 0,132 W m-2K-1 och värmeledningstalet centre-av-panel 7 mW m-1K-1 uppnåddes. Detta arbete innehåller dessutom en ny metod för att mäta köldbryggor i anslutningar med hjälp av infraröd termografi. En effektiv värmeledningsförmåga för 10.9 mW m-1K-1 uppnåddes. Resultaten tyder även på att den verkliga termiska prestandan av VIP:ar i konstruktioner är något sämre än mätvärden för paneler i laboratorium. En effektiv värmeledningsförmåga av 10.9 mW m-1K-1 ger dock väggkonstruktionen en utmärkt termisk prestanda. Det tredje syftet har varit att bedöma miljöpåverkan av en VIP-isolerad byggnad, från produktion till drift, eftersom en livscykelanalys av hela byggnader som är isolerade med vakuumisoleringspaneler inte har gjorts tidigare. Slutsatsen var att VIP:ar har en större miljöpåverkan än traditionell isolering, i alla kategorier förutom ozonnedbrytande potential. VIP:ar har en mätbar påverkan på de totala utsläppen av växthusgaser och primärenergianvändningen i byggnader när både produktion och drift beaktas. Miljöpåverkan av de använda VIP:arna är dock positiv jämfört med GWP av en standardbyggnad (en minskning med 6 %) medan primärenergianvändningen ökade med 20 %. Slutsatsen var att ytterligare användning av VIP:ar gynnas av reducerad energiförbrukning och alternativa energikällor i produktionen av nanoporösa kiselpulver medan användningen av alternativa kärnmaterial och återvinning av VIP kärnor kan hjälpa till att minska miljöpåverkan. En känslighetsanalys visade att valet av VIP:ar har en betydande inverkan på miljöpåverkan, vilket ger möjlighet att reducera den totala användningen av primärenergi i en byggnad med 12 % och utsläppen av växthusgaser kan vara minska, så mycket som 11 % när det gäller både produktion och drift under 50 år. Avslutningsvis är det möjligt att dra slutsatsen att VIP:ar är ett mycket konkurrenskraftigt alternativ för att isolera byggnader som är typiska för Miljonprogrammet. Dock krävs ytterligare undersökningar för att minimera de mätbara miljöeffekter som förvärvats i denna LCA-studie för VIP-isolerade byggnader.

QC 20151109

Simulations of heat and moisture conditions in a retrofit wall construction with Vacuum Insulation Panels
Textural and thermal conductivity properties of a low density mesoporous silica material
A study of the thermal conductivity of granular silica materials for VIPs at different levels of gaseous pressure and external loads
Evaluation of the thermal conductivity of a new nanoporous silica material for VIPs – trends of thermal conductivity versus density
A comparative study of the environmental impact of Swedish residential buildings with vacuum insulation panels
ETICS with VIPs for improving buildings from the Swedish million unit program “Miljonprogrammet”

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Allaire, André. "Vacuum refining of copper matte." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65401.

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Bergman, Joel, and Johan Lind. "Robot Vacuum cleaner." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264502.

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Although a robot vacuum cleaner is a well-known product, development is still interesting. Better working sensors and more sophisticated algorithms and sensors are used in new cleaners. The purpose with this thesis was to learn more about different sensors, algorithms, and designs of robot vacuum cleaners, to try ideas and to find improvements to implement on the demonstrator. The initial work was to make a market investigation to find customer needs and expectations. Also making a rough design and layout for the mechanical and electrical system. The budget for the demonstrator was 1000 SEK. Using laser cut plastic sheets, 3D printed parts, and receiving motors for free, costs did not exceed budget. Literature and theses in the area of interest were studied to find answers to some of the research questions. The theses studied subjects such as driving pattern and designs to find back to charge station. Some ideas for driving patterns were implemented on a demonstrator. The development method used was iteration of finding useful information, testing components, codes and also the complete demonstrator. The components used were DC motor, stepper motors, ultrasonic sensors, Arduino mega micro controller, switches and AA batteries. The different components required different voltage and the stepper motors used driver cards.
Även om robot dammsugare är en välkänd produkt är produktutveckling fortfarande intressant. Bättre sensorer och mer sofistikerade algoritmer och sensorer används i dammsugare. Syftet med denna avhandling var att lära sig mer om olika dammsugare, algoritmer och konstruktioner av robot dammsugare, för att prova idéer och möjliga hitta förbättringar att implementera på demonstranten. Det första arbetet var att göra en marknadsundersökning för att hitta kundens behov och förväntningar. Även att göra en grov design och layout för det mekaniska och elektriska systemet. Budgeteringen för demonstranten var 1000 kr. Kostnaderna översteg inte budgeten eftersom vi använde oss av laser skurna plastplattor, 3D-printade delar och erhöll motorer utan kostnad. Sex olika avhandlingar studerades för att hitta svar på några av frågorna. Avhandlingarna studerade ämnen som körmönster och mönster för att hitta tillbaka till laddstationen. Vissa idéer för körmönster implementerades på demonstranten. Den använda utvecklingsmetoden var iteration av att hitta användbar information, testa komponenter, koder och även den fullständiga demonstranten. De komponenter som användes var likströmsmotor, stegmotorer, ultraljudssensorer, Arduino mega-mikrokontroller, strömbrytare och AA-batterier. De olika komponenterna krävde olika spänningar och stegmotorn använder ett specifikt drivkort.

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Mathers, Philip. "The effect of acoustic standing waves on vacuum coating technology." Thesis, Cranfield University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263535.

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Wright, Robert S. "Vacuum Steam Technology for Rapid Plasticization and Bending of Maple." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/43701.

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Bending wood dates back to antiquity in the form of baskets from willow branches and when boats were no longer made of hollowed out logs. Fresh growth willow twigs are readily bent into practically any shape; however, when wood has been separated from the tree and dried it is more rigid, difficult to bend, and breakable. Steamed wood is less rigid since adding moisture and heat to wood results in plasticization. Steaming at atmospheric pressure is the common technique for wood bending where diffusion prevails as the predominant mechanism governing moisture movement. Applications using conventional atmospheric steaming are time consuming and can result in failed bends. While other wood plasticization methods exist, Vacuum Steam Technology offers a promising method that utilizes pressure differentials to accelerate the addition of steam to wood due to water vapor bulk flow and subsequently an accelerated temperature rise and moisture addition. The objectives of this work were: (1) determine whether cycles of vacuum and steaming could significantly improve the plastic-deformable state relative to the classic process of atmospheric steaming given equivalent treatment times when beginning with low moisture content (<10%) maple, and (2) compare the work required to bend to form between Vacuum Steam Technology treated maple and atmospheric-steamed maple when beginning with low moisture content (<10%) specimens. A procedure for Vacuum Steam Technology to enable rapid plasticization of maple specimens from a kiln-dried state was developed. Kiln dried maple specimens were either treated according to the Vacuum Steam Technology procedure or were atmospherically steamed for a time equivalent to the Vacuum Steam Technology treatment and then bent into a 180Â° semi-circular form. Vacuum Steam Technology treated specimens had 0 failed bends whereas the atmospheric steamed specimens resulted in 39% failed bends. Vacuum Steam Technology treated specimens resulted in 17% less work to bend. The results clearly indicate that Vacuum Steam Technology is a superior technique for attaining a plastic deformable state prior to bending when beginning with low moisture content maple. Additional results included time to temperature, rate of moisture content change, final moisture contents, specific gravity influence.
Master of Science

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Haas, Steven Frederick 1955. "Effects of a squeezed vacuum on absorptive optical bistability." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276900.

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The effects of a squeezed vacuum on absorptive optical bistability (AOB) are calculated using the different relaxation rate approximation for in-quadrature and in-phase components of a two-level system developed by Gardiner. An expression for the complex absorption coefficient is developed, and the result applied to the AOB equation for the unidirectional ring cavity. We find a significant degradation of bistability for values of the in-quadrature decay constant less than or equal to approximately.5 of the in-phase decay constant. Effects of detuning and relative phase of the pump field to the squeezed vacuum field are also examined.

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Schmalz, Kurt, and Albrecht Winter. "Trends in Vacuum Technology and Pneumatics in the Context of Digitalization." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-200405.

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Digitalization is finding it’s way into production and machine-building. Autonomous, sefoptimizing and highly interconnected units will determine the functionality of machines and production facilities. Communication and automation layout will fundamentally change, data will be more and more the base for new business modells. Innovation is determining pneumatics and handling technology. The innovation topics performance improvement, modular and mechatronic design of systems, sustainability and efficiency are keeping pneumatics and vacuum technology on the pathway of success. But is the technology field also prepared for the tremendous challenges caused by the digitalization? This paper is focusing on the significance of digitalization for fluid technology, especially for pneumatics and vacuum technology. The new concepts of digitalization and autonomization are based on the Internet of Things with open Communication of cyber-physical systems. These cyber-physical systems are able to react autonoumously. Cyber-physical systems can collect, interpret and analys data and transfer it into valuable information. Based on these data, cyberphysical systems will provide services to all participants of the smart factory. There will be a digital image inside the factory cloud, which is the base of new business models. Systems of pneumatics, vacuum technology and hydraulics will play a core role in this world. They are placed directly at the interface to the real technical process, they have direct contact with the workpieces, they are collecting multitude of sensor data and are evaulating it, they have functionality like Condition Monitoring and Energy Efficiency optimization on board and are able to communicate with the world of automation. This paper will show, that the innovation trends of the last years are supporting the way towards digitalization and Industrial Internet of Things. There are already a lot of different approaches to establish vacuum and pneumatic systems as adequate elements of the digitalized world. It will also be shown, that fluid technology still is facing tremendous challenges It will be not sufficient to equip the systems with more functionality and better communication. It will be essential, that from the interpretation and correlation of data will be derived valuable services with real customer benefit. This should happen under control of the vendors of smart field devices in fluid technology. Then it will be possible to turn this new kind of value generation also into new business models.

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Emre, Sunal Egill. "Attefallshus insulated with Vacuum Insulated Panels." Thesis, KTH, Byggnadsteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-196019.

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Stockholm lies at the top in Europe in terms of population growth. It is growing from 30,000 to 40,000 residents each year and therefor puts high demands on the regions development. One of the governments reactions to this housing problem was to approve a bill that would simplify the regulatory framework in the planning and building act. It will among other permit owners of a one-or two family houses to build a 25 compliment housing without a building permit, so called attefallshus. In this final project, a small 25 house is designed. The house was designed to have thin exterior walls to maximize the indoor living space and also to fulfill all the Boverkets regulations for permanent housing. Vacuum Insulated panels were used as an insulation material in the envelope to achieve the extra thin exterior walls to maximize the living space. Various different simulations were done to simulate: Heat- and moisture transfer through the exterior walls, thermal bridges, energy calculations and the daylight factor inside the house. Additional calculations were done in Excel to compare the mean U-value calculated in simulations. The moisture transfer simulation did show that there should not be any moisture problems in the exterior walls. The mean U-value calculations in Excel and in the simulations showed values less than the limitations of Boverkets building regulations.

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Demir, Vedat. "Development and application of vacuum heat-treated silicon nitride ceramics." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310039.

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Daniel, Muzito Kim. "Digitalisation online condition monitoring and AI analysis in a vacuum pump." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-28826.

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Billerudkorsnäs is a good example of an industry that associated with a 24/7 production and where faults lead to downtime in the production process which in its turn generates substantial losses. Sustainability is essential for a prosperous future for Billerudkorsnäs, and with the growth of technologies and digitalization with big data that are in line with the coming Industry 4.0 standard, the company will have the possibility to ensure a sustainable production system. However, to be able to achieve this, it is necessary to implement an intelligent maintenance system into the traditional manufacturing process. This study will, therefore focus on how online monitoring can be applied to estimate error prediction on Nash vacuum pumps by using Bluetooth low energy sensors. At Billerudkorsnäs, 6 Nash vacuum pumps have from time-to-time had a problem of bearing faults resulting in unreliable production. Even though time-based maintenance has been implemented, it has proven to be an insufficient method to uphold an efficient production and to in-time detect faults in the production process. As a response to this, first, the study has deployed a digitalized online monitoring application for fault prediction. By utilizes of Bluetooth low energy (BLE) Beacon, communication gateway (BLuFi) and a web-based platform Bluzone with cloud server services that work parallel with machine learning technology. The faults discovered by implemented application are observed via Bluzone. In addition, automatic generated e-mail sent to a vacuum pump inspector when such faults have occurred. Second, as an effect of this implementation, a classical theoretical framework based on an AutoRegressive (AR) and AR with exogenous input (ARX) for prediction modelling has been studied. The method applies historical data from the vacuum pump, and the problem with input and output data from two different applications is discussed. The results of the study gave at hand- in comparison with the technology used to-day – that the implemented new system has a more efficient in providing reliable information as to prevent unnecessary downtime in the Nash vacuum pumps. This implies a lower production cost. Although interesting results in practice it is difficult to use theoretically. In correspondence, AR prediction model results verify the model fit compared to the measured response. Also, the ARX model was tested.
BillerudKorsnäs är ett bra exempel på ett företag i en bransch som kan associeras med en 24/7-produktion och där fel i produktionsutrustningen leder till nedtid i produktionen vilken i sin tur genererar stora förluster. Hållbarhet är därmed en förutsättning för en framtidsäkrad verksamhet i Billerudkorsnäs. Med den teknikutveckling och digitalisering som blir följden av den kommande Industry 4.0-standarden, kommer företag generellt att kunna ha ett mer hållbart produktionssystem. För att kunna uppnå detta är det dock nödvändigt att implementera ett intelligent underhållssystem inom den traditionella tillverkningsprocessen. Denna studie ämnar därmed att fokusera på hur löpande online-monitorering kan tillämpas för att ge bra underlag för felsökning på Nash-vakuumpumpar med hjälp av digitaliserad Bluetooth låg energi - sensorer. Hos Billerudkorsnäs har 6 Nash-vakuumpumpar haft problem genom åren som givit upphov till otillförlitlig produktion. Trots att underhåll baserat på tidsaspekter kontinuerligt har genomförts, så har det visat sig vara en otillräcklig metod för att upprätthålla en effektiv produktion och att upptäcka fel över tid i produktionsprocessen. Som svar på detta, först har denna rapports ambition varit att studera vad en implementering av en digitaliserad (online) övervakningsapplikation för felprognoser kan påverka tillförlitligheten i produktionen. Metoden som använts har varit att implementera BLE Beacon, kommunikationsgateway (BLuFi) in i webbplattformen Bluzone som är servermiljön och ha det som en molntjänst. BLE Beacon arbetar med maskininlärningsteknik. De fel som upptäckts genom användandet av denna metod dokumenteras via Bluzone. Vidare har automatgenererade epostmeddelanden skickats till en vakuumpumpinspektör när fel uppträtt. Som en effekt av metodens implementation har en teoretisk modell baserad på AutoRegressive (AR) och AR med exogenous input (ARX) för prediktionsmetoder etablerats. Resultaten av studien visade, i jämförelse med dagens teknik, att den nya metoden har en högre effektivitet när det gäller att tillhandahålla de ansvariga med tillförlitlig information för att förhindra onödiga driftstopp i Nashvakuumpumparna. Detta har i sin tur medfört en lägre produktionskostnad. Det är intressanta resultat i praktiken men, det är svårt att använda teoretiskt. I korrespondens, verifierar AR-prediktionsmodell resultaten ”model fit” i jämförelse med det uppmättadata. Dessutom testades ARX-modellen.

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Balthazar, Vadinal Rodolfo. "Desenvolvimento de modelos para torre de vácuo de refinaria de petróleo = da abordadgem robusta ao treinamento de operadores." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266913.

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Orientador: Maria Regina Wolf Maciel
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: Nos últimos dois anos, o Brasil vem estampando as manchetes dos principais veículos de comunicação mundiais com os anúncios das novas descobertas de reservatórios de petróleo na camada do Pré-Sal. Enormes investimentos estão sendo direcionados para viabilizar a exploração e a produção de petróleo em profundidades ultra-profundas. Enquanto isso, as refinarias brasileiras (e mundiais) se ajustam às características dos óleos processados atualmente: cada vez mais pesado e com maiores teores de contaminantes. Para atender às crescentes demandas das indústrias e mercados consumidores, os processos de refino de fundo de barril, dentre os quais se destaca a unidade de craqueamento catalítico (FCC), ganham importância. O craqueamento catalítico converte frações pesadas em frações mais leves e de maior interesse industrial. A principal unidade de uma refinaria que fornece as matérias-primas necessárias para o funcionamento do FCC é a unidade de destilação a vácuo (UDV), usadas para recuperar frações de óleo pesadas, especialmente o gasóleo de vácuo leve (GOL) e o gasóleo de vácuo pesado (GOP). A torre de vácuo é utilizada para o processamento de óleos pesados e ultrapesados, fazendo uso de pressões sub-atmosféricas para evitar a decomposição térmica dos constituintes do petróleo. Apesar do desenvolvimento e avanço tecnológico das refinarias, modelos computacionais que permitam uma análise mais detalhada para melhorar a compreensão do funcionamento da torre de vácuo são necessários. Sendo assim, o objetivo deste trabalho é apresentar novos esquemas computacionais para a representação da torre de vácuo, realizando um procedimento de análise de sensibilidade das variáveis de processo e identificando um novo ponto operacional que maximize a produção de gasóleos de vácuo (GVAC). A metodologia proposta neste projeto consiste na utilização de três resíduos atmosféricos (RAT) de diferentes características e na implementação da UDV no simulador de processos Aspen Plus, versão 22.0. Para representar a torre de vácuo, fez-se uso de quatro colunas de destilação a vácuo distintas, cada uma representando, do topo para a base: seção de retirada de GOL; seção de retirada de GOP; zona de lavagem; e seção de esgotamento. Após a implementação da torre e a criação de especificações para os produtos GOP e GOL, foi realizada uma análise de sensibilidade para avaliar a influência das variáveis operacionais no processo de recuperação do RAT. Os parâmetros estudados foram: injeção de vapor de retificação; vazão e temperatura do refluxo circulante da seção de retirada de GOL e de GOP; vazão de óleo de lavagem; vazão de hot reflux; vazão de sobrevaporizado; porcentagem de entrainment e temperatura do forno. Para um RAT particular foi possível aumentar a produção de GVAC em até 14%. O desenvolvimento dos modelos computacionais e os resultados das simulações são importantes por dois motivos: primeiro, por não serem facilmente encontrados na literatura aberta e, segundo, pela possível utilização no treinamento de operadores
Abstract: In the last two years, Brazil has been stamping the headlines of major media world with announcements of new discoveries of oil reservoirs in the Pre-Salt layer. Huge amounts of investments are being directed to facilitate the exploration and production of oil in ultra-deep depths. Meanwhile, refineries in Brazil (and worldwide refineries) now process oils that getting heavier and with higher levels of contaminants. To meet the growing demands of industries and consumer markets, conversion processes, among which stands out the fluid catalytic cracking unit (FCC), are highlighted. The catalytic cracking converts heavy fractions into lighter fractions and larger industrial interest. The main unit of a refinery that supplies the raw materials necessary for the operation of the FCC is the vacuum distillation unit (VDU), used to recover heavy oil fractions, especially the light vacuum gasoil (LVGO) and heavy vacuum gasoil (HVGO). The vacuum tower is used for processing heavy and ultra-heavy oils, making use of sub-atmospheric pressures to avoid thermal decomposition of petroleum constituents. Despite the technological advancement and development of refineries, computational models that allow a more detailed analysis to better understand the operation of the vacuum tower are necessary. Therefore, the objective of this work is to present new computational schemes for representation of the vacuum tower, performing a procedure for sensitivity analysis of process variables and to identifying a new operational point that maximizes the production of vacuum gasoil (VGO). The methodology proposed in this project is the use of three atmospheric residue (ATR) of different characteristics and the implementation of the VDU in the process simulator Aspen Plus, version 22.0. To represent the vacuum tower, four vacuum distillation columns are used, each one represents, from top to bottom: withdrawal section of LVGO; withdrawal section of HVGO; washing zone; and stripping section. After the implementation of the vacuum tower and the creation of specifications for LVGO and HVGO products, a sensitivity analysis was performed to evaluate the effect of operating parameters on the recovery process of ATR. The parameters studied were: injection of stripping steam; flow and temperature of the LVGO pumparound circuit; flow and temperature of the HVGO pumparound circuit; flow of washing oil; flow of hot reflux; overflash percentage; percentage of entrainment and furnace temperature. For a particular ATR, it was possible to increase the VGO production by up to 14%. The development of computational models and simulation results are important for two reasons: firstly, because they are not easily found in the open literature and, secondly, for the possible use in operator training
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química

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Perumal, Rajkumar. "Comparative performance of solar cabinet, vacuum assisted solar and open sun drying methods." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18283.

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Tomato (Lycopersicon esculentum L.var) is one of the most important vegetables in our diet and dried tomato products are becoming popular for the preparation of various food items. Though sun drying has been used for the preservation, it is a slow process and the quality of the dried product is often inferior due to contaminations. Therefore, a lab model solar cabinet and vacuum assisted solar dryers were developed to study the drying kinetics of tomato slices (4, 6 and 8 mm thicknesses) and the results were compared individually with open sun drying under the weather conditions of Montreal, Canada. The drying kinetics using thin layer drying models and the influence of weather parameters such as ambient air temperature, relative humidity, solar insolation and wind velocity on drying of tomato slices were evaluated. During drying, it was observed that the temperatures inside the solar cabinet and vacuum chamber were increased to 63 and 48oC when the maximum ambient temperature was only 30oC. The tomato slices of 4, 6 and 8 mm thicknesses could be dried from 94.0 to 11.5% wet basis moisture content, respectively in 300, 420 and 570 min using solar cabinet, in 360, 480 and 600 min using vacuum assisted solar dryer and it took 435, 615 and 735 min under open sun drying method. The quality of tomato slices in terms of physicochemical parameters such as colour retention, water activity, rehydration capacity and ascorbic acid retention were evaluated and the overall study concluded that good quality dehydrated tomato slices could be produced by using vacuum assisted solar dryer compared to solar cabinet and open sun drying methods. The Page model was found to be better in describing the drying kinetics of tomato slices in all the drying methods studied.
La tomate (Lycopersicon esculentum L. var) est une importante source nutritive de notre alimentation et les tomates séchées gagnent en popularité dans de nombreuses préparations alimentaires. Le séchage naturel est la méthode traditionnelle utilisée pour la production de tomates séchées, cependant c’est un processus lent et la qualité du produit séché est variable et sujette à la contamination. Un séchoir solaire et un séchoir solaire sous-vide furent donc développés afin d’étudier le séchage solaire de tranches de tomates (4, 6 et 8 mm d’épaisseur) en comparaison au séchage naturel sous les conditions météorologiques de Montréal, Canada. La cinétique du séchage des tranches de tomates suivant des modèles en couches minces a été établie en fonction de l’influence des conditions météorologiques telles que la température ambiante, l’humidité relative, le rayonnement solaire et la vitesse du vent. Lors du séchage dans le séchoir solaire et le séchoir solaire sous-vide, la température interne des deux séchoirs a atteint 63° et 48°C respectivement alors que la température ambiante était de 30°C. Les tranches de tomates de 4, 6 et 8 mm d’épaisseur ont pu être séchées d’un taux d’humidité de 94% à 11.5% (état humide) et ce après 300, 420 et 570 minutes en utilisant le séchoir solaire, en 360, 480 et 600 minutes grâce au séchoir solaire sous-vide, alors qu’il en a pris 435, 615 et 735 minutes par séchage naturel. La qualité des tranches de tomates a été évaluée en fonction de certains paramètres physico-chimiques tels que la stabilité de la couleur, l’activité de l’eau, la capacité de réhydratation, et la conservation de l’acide ascorbique. Des tranches de tomates séchées de meilleure qualité peuvent être produites par séchage solaire sous-vide en comparaison avec le séchage solaire et le séchage naturel. La modélisation de Page offre une très bonne représentation$

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Johnston, David A. "The use of metal evaporation in the design and manufacture of enzyme electrodes." Thesis, University of the West of Scotland, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323763.

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Hoagland, David Wayne. "Continuous Permeability Measurement During Unidirectional Vacuum Infusion Processing." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6457.

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Composite materials have traditionally been used in high-end aerospace parts and low-end consumer parts. The reason for this separation in markets is the wide gap in technology between pre-preg materials processed in an autoclave and chop strand fiberglass blown into an open mold. Liquid composite molding has emerged as a bridge between inexpensive tooling and large, technical parts. Processes such as vacuum infusion have made it possible to utilize complex layups of reinforcement materials in an open mold style set-up, creating optimal conditions for composites to penetrate many new markets with rapid innovation. Flow simulation for liquid composite molding is often performed to assist in process optimization, and requires the permeability of the reinforcement to be characterized. For infusion under a flexible membrane, such as vacuum infusion, or for simulation of a part with non-uniform thickness, one must test the permeability at various levels of compaction. This process is time consuming and often relies on interpolation or extrapolation around a few experimental permeability measurements. To accelerate the process of permeability characterization, a small number of methodologies have been previously presented in the literature, in which the permeability may be tested at multiple fiber volume contents in a single test. Some of the methods even measure the permeability over a continuous range of thicknesses, thus requiring no later interpolation of permeability values. A novel method is presented here for the rapid measurement of permeability over a continuous range of fiber volume content, in a single unidirectional vacuum infusion flow experiment. The thickness gradient across the vacuum bag, as well as the fluid pressure at several locations in the mold, were concurrently measured to calculate the fabric compressibility. An analytical flow model, which accounts for the compressibility, is then used by iterating the fitting constant in a permeability model until the predicted flow front progression matches empirical measurement. The method is demonstrated here for two reinforcement materials: 1) a fiberglass unbalanced weave and 2) a carbon bi-ax non-crimped fabric. The standard deviation of calculated permeabilities across the multiple infusion experiments for each material and flow orientation ranged from 12.8% to 29.7%. Validation of these results was performed by comparing the resulting permeability with multiple non-continuous permeability measurement methods.

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Seavey, Kevin Christopher. "Research and Development of Simulation and Optimization Technology for Commercial Nylon-6 Manufacturing Processes." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/26930.

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This dissertation concerns the development of simulation and optimization technology for industrial, hydrolytic nylon-6 polymerizations. The significance of this work is that it is a comprehensive and fundamental analysis of nearly all of the pertinent aspects of simulation. It steps through all of the major steps for developing process models, including simulation of the reaction kinetics, phase equilibrium, physical properties, and mass-transfer- limited devolatization. Using this work, we can build accurate models for all major processing equipment involved in nylon-6 production. Contributions in this dissertation are of two types. Type one concerns the formalization of existing knowledge of nylon-6 polymerization mixtures, mainly for documentation and teaching purposes. Type two, on the other hand, concerns original research contributions. Formalizations of existing knowledge include reaction kinetics and physical properties. Original research contributions include models for phase equilibrium, diffusivities of water and caprolactam, and devolatization in vacuum- finishing reactors. We have designed all of the models herein to be fundamental, yet accessible to the practicing engineer. All of the analysis was done using commercial software packages offered by Aspen Technology, Cambridge, MA. We chose these packages for two reasons: (1) These packages enable one to quickly build fundamental steady-state and dynamic models of polymer trains; and (2) These packages are the only ones commercially available for simulating polymer trains.
Ph. D.

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Görhardt, Stefan [Verfasser], and G. [Akademischer Betreuer] Drexlin. "Background Reduction Methods and Vacuum Technology at the KATRIN Spectrometers / Stefan Görhardt. Betreuer: G. Drexlin." Karlsruhe : KIT-Bibliothek, 2014. http://d-nb.info/1047383462/34.

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Maia, Júlio Pereira 1978. "Simulação e analise da coluna de destilação a vacuo da unidade de destilação de processos de refino de petroleo." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267176.

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Orientador: Maria Regina Wolf Maciel
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Unidades de vácuo para destilação de petróleo são estudadas neste trabalho. A destilação a vácuo é empregada para frações pesadas do petróleo, com vastas aplicações em processamento de crus pesados e ultra-pesados, motivado pelas dificuldades em se processar estes crus a pressão atmosférica devido ao alto ponto de ebulição dos componentes em suas composições. Estes compostos podem ser facilmente decompostos se não forem destilados abaixo da pressão atmosférica. Os produtos obtidos desta unidade são usados como insumos para a Unidade de Craqueamento Catalítico (UCC). Adotaram-se dois tipos de crus neste trabalho. Estes crus foram estabelecidos e caracterizados em um ambiente de simulação. Diferentes blends dos óleos foram considerados. Como unidades de vácuo estão conectadas com unidades atmosféricas, ambas as unidades foram simuladas no estado estacionário. A unidade atmosférica foi simulada com os equipamentos auxiliares principais. Produtos da unidade atmosférica foram determinados, e procedimentos para ajustar as variáveis de sistema de forma a fazer com que os produtos estivessem especificados foram apresentados. O projeto convencional de unidade de vácuo para produção de combustíveis foi o adotado para a simulação. Procedimentos para auxiliar a convergência da simulação desta unidade foram desenvolvidos. Uma análise de sensitividade foi conduzida, analisando as principais variáveis do sistema. Baseado nisso, um procedimento de otimização no estado estacionário foi adotado, levando em consideração os limites de convergência determinados para a análise de sensitividade. O sistema foi convertido do estado estacionário para se realizar uma simulação dinâmica. A simulação dinâmica foi conduzida com mudanças no fluxo de alimentação da torre atmosférica. O estabelecimento desta plataforma de simulação e sua disponibilidade foram muito importantes, bem como os resultados da simulação, por não ser facilmente encontrado na literatura aberta. Mais ainda, a grande complexidade deste processo de separação faz com que seja útil para treinamento de operadores.
Abstract: Vacuum units for petroleum distillation are studied in this work. Vacuum distillation is employed for heavy petroleum fractions, with large applications on heavy and ultra-heavy crude processing, motivated by difficulties in processing these crudes at atmospheric pressure, due to the boiling range of the compounds in their compositions. These compounds would be easily decomposed if they were not distillated under atmospheric pressure. The products obtained from this unit are used as feedstock for Fluid Catalytic Cracking Unit (FCCU). Two different petroleum crudes were adopted in this work. These petroleum were established and characterized in a simulation environment. Different blends from the oils were considered. As vacuum units in petroleum plants are connected with atmospheric units, both units were simulated in steady state. The atmospheric unit was simulated with the main auxiliary equipment. Products from atmospheric unit were set, and a procedure to set system variables in order to make the products to meet specifications was presented. The conventional design vacuum unit for fuels production was set to be simulated. Procedures to aim convergence of the simulation of this unit were developed. A sensitivity analysis was carried out, analyzing the main variables of the system. Based on it, an optimization procedure in steady state was applied, taking into consideration the convergence bounds set for the sensitivity analysis. The system was converted from steady state to perform a dynamic simulation. The dynamic simulation was carried out with changes in the atmospheric feed flow rate. The establishment of this simulation platform and its availability were very important as well as the results of the simulation, since this is not easily found in the open literature. Moreover, the large complexity of this separation process makes it useful for operator training.
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química

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Smith, Katharine Lucy. "Characterisation of electrospray properties in high vacuum with a view to application in colloid thruster technology." Thesis, Queen Mary, University of London, 2005. http://qmro.qmul.ac.uk/xmlui/handle/123456789/1868.

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The operational environment of colloid thrusters is high vacuum (10-3 _ 10-6 mbar) however, much of the experimental data collected to date to identify parameter relationships in cone jet mode electrosprays (ES), such as current-volumetric flow rate scaling laws, has been conducted in atmospheric conditions. This highlights a need for electrospray data under high vacuum conditions. Electrospray experimental data was collected using medium conductivity solutions (0.0025 -0.0160 S/m) of TEG doped with sodium iodide in high vacuum. These sprays were obtained from a stainless steel capillary and a disk counter electrode with central aperture. An online flow measurement system is described, which has been developed during this research to measure the fluid volumetric flow rate, concurrently with applied voltage and spray properties such as spray current and cone, jet and spray geometry. This automated flow measurement system was used to measure flow rates as low as InUs with an absolute accuracy of 0.3nUs and a resolution of 0.03nus. It is identified that this system may be easily adapted for lower flow rates and higher resolutions. The ES data collected demonstrates, for the first time, the detailed dependence of volumetric flow rate upon the applied voltage. The sensitivity of nominal flow rate to applied voltage was found to be higher for lower nominal flow rates. For a volumetric flow rate -4nLIs a 25% a change in flow rate per kV was recorded over a cone-jet mode stability range spanning -1.5kV. This volumetric flow rate voltage sensitivity holds particular significance for colloid thruster systems, which operate at or near minimum flow rate conditions. The current was found to have a power law dependence on flow rate similar to the current scaling laws of F. de la Mora and Gahan-Calvo however the exponent of this power law differs significantly from these scaling laws. A study considering the effect of charge carrier mobility in simple 1: 1 electrolytes shows that the exponent of the power law current-flow rate scaling increased with increasing charge carrier mobility. Contrary to the various scaling laws the spray current was found to be dependent on electrostatic conditions. The sensitivity of the emitted current to the applied voltage was also found to increase with increasing nominal volumetric flow rate. The geometrical parameters of cone angle, spray angle and jet length were measured for varying TEG/Nal solution conductivity. Cone geometry was found to be relatively independent of conductivity in the range tested. Jet length was found to have an inverse relationship with solution conductivity.

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Tina, Monteiro Shelsea. "Real Time Measurement of Dirt Pick-up by a Robotic Vacuum Cleaner using Light Sensing Technology." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254349.

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Domestic chores are one of the most tedious and time consuming tasks in a person’s life. A lot of time can be saved and put to better use if these tasks can be automated. One such chore is the routine task of vacuuming the house every day. Robotic vacuum cleaners that clean the house are thus one of the most widely used domestic robots. These robots have the ability to clean the entire house almost autonomously with little or no human intervention. However, most of these robots do not have a system to report the real-time pick up of dirt which can be useful to the user in knowing which parts of his house are dirty and maybe investigate the reason behind it. This information can be useful to the robot as well in determining efficient cleaning patterns based on the dirt localization in the house. In this thesis a prototype was developed to measure the real-time pick-up of dirt by a robotic vacuum cleaner. It uses light sensing technology to measure the amount of dirt picked up and can thus be used to glean which parts of the house are dirtier than the others. The signals can also potentially be used to understand the size of the dirt picked up by the robotic vacuum cleaner. Research was done to investigate the different sensing technologies that can be used and to select the appropriate one. The system was tested and conclusions were made regarding its performance. Additional functions that can be implemented and improvements that can be made have also been suggested as future work.
Att städa hemmet är en av de mest tråkiga och tidskrävande uppgifterna i en persons liv. Mycket tid kan sparas och användas bättre om dessa uppgifter kan automatiseras. Robotdammsugare som städar golvet i hemmet är en av de mest använda inhemska robotarna, då dessa robotar har möjlighet att rengöra hela huset nästan autonomt med liten eller ingen mänsklig intervention. De flesta av dessa robotar har dock inte ett system för att rapportera realtidsupphämtning av smuts som kan vara användbart, då användaren kan få reda på vilka delar av huset som är smutsiga och då ha möjlighet att undersöka orsaken bakom. Denna information kan också vara användbart för roboten för att bestämma effektiva rengöringsmönster baserat på lokalisering av smuts i huset. I denna avhandling utvecklades en prototyp för att mäta upptagning av smuts i realtid av en robotdammsugare. Den använder IR-teknik för att mäta mängden smuts som hämtas upp och kan därmed använda informationen för att avgöra vilka delar av huset som är smutsigare än andra. Signalerna kan också potentiellt användas för att förstå storleken på smuts som tas upp. Forskning av olika tekniker utfördes för att kunna välja den mest lämpliga. Systemet testades därefter och slutsatser gjordes avseende dess prestanda. Ytterligare utredningar och förbättringar som kan genomföras har också föreslagits som framtida arbete.

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Paiva, Jadilson Alves de. "Aplicação da tecnologia do vácuo em projeto de engenharia de precisão." Universidade Federal da Paraíba, 2010. http://tede.biblioteca.ufpb.br:8080/handle/tede/5402.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
This work presents the state of the in vacuum technology which covers the fundamentals, devices for generating, measuring and major applications in precision engineering. Also, the design and development of vacuum tables applied to machine tool is shown. With regard to fundamentals, it is described the historical background, classical theories and classification of this technology by bands of applications. It is shown most widely used vacuum generators and gauges, showing their construction, operation and applications within various areas. Applications of vacuum technology in precision engineering that span the macro, micro and nano scales are presented, highlighting their importance in each application area. In addition, a methodology to design and development of vacuum tables to fixture workpieces in machine tools, is described and applied. The development of this methodology was motivated due lack of technical and scientific articles that concern the studies on vacuum tables with emphasis on its design parameters. In this work, vacuum tables with hollow, square and hexagonal cores were analyzed by considering two different magnitudes of machining forces. The displacement and stress that each vacuum table configuration is submitted were determined by using numeric simulation based on the finite element method for both machining conditions.
O presente trabalho trata do resgate da literatura sobre a tecnologia do vácuo englobando os seus fundamentos básicos, dispositivos de geração, medição e o estado da arte em aplicações na área de engenharia de precisão seguido de um projeto e desenvolvimento de mesas de vácuo aplicadas em máquinas-ferramenta. Com relação aos fundamentos, é descrito o seu contexto histórico, teorias clássicas e classificação desta tecnologia por faixas de aplicações. É mostrado os geradores e medidores de vácuo mais utilizados evidenciando a sua construção, funcionamento e aplicações dentro das mais variadas áreas. São apresentadas aplicações na engenharia de precisão que abrangem as escalas macro, micro e nano, ressaltando a importância da tecnologia do vácuo em cada aplicação. No projeto e desenvolvimento de mesas de vácuo, é descrita e aplicada uma metodologia própria que consiste em dimensionar mesas de vácuo capazes de fixar peças mediante a usinagem em máquinas-ferramenta. O desenvolvimento desta metodologia foi motivada em função da carência de artigos técnicos e científicos que concernem os estudos sobre mesas de vácuo dando ênfase aos seus parâmetros de projetos. São dimensionadas mesas de vácuo com núcleos vazados, quadrado e hexagonal em função de duas condições de usinagem que utilizam diferentes magnitudes de forças. Por meio de simulação numérica computacional, são avaliados os esforços de deslocamento e tensão em cada mesa de vácuo dimensionada, de forma a eleger uma mesa que atenda a critérios de rigidez, peso e homogeneização do fluxo de vácuo para cada magnitude de forças de usinagem.

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Lautenschlager, Eric J. "Silicon nanoclusters : ultra high vacuum laser ablation fabrication and in situ scanning tunneling microscopy characterization /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.

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Torunbalci, Mert Mustafa. "Wafer Level Vacuum Packaging Of Mems Sensors And Resonators." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613015/index.pdf.

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This thesis presents the development of wafer level vacuum packaging processes using Au-Si eutectic and glass frit bonding contributing to the improvement of packaging concepts for a variety of MEMS devices. In the first phase of this research, micromachined resonators and pirani vacuum gauges are designed for the evaluation of the vacuum package performance. These designs are verified using MATLAB and Coventorware finite element modeling tool. Designed resonators and pirani vacuum gauges and previously developed gyroscopes with lateral feedthroughs are fabricated with a newly developed Silicon-On-Glass (SOG) process. In addition to these, a process for the fabrication of similar devices with vertical feedthroughs is initiated for achieving simplified packaging process and lower parasitic capacitances. Cap wafers for both types of devices with lateral and vertical feedthroughs are designed and fabricated. The optimization of Au-Si eutectic bonding is carried out on both planar and non-planar surfaces. The bonding quality is evaluated using the deflection test, which is based on the deflection of a thinned diaphragm due to the pressure difference between inside and outside the package. A 100% yield bonding on planar surfaces is achieved at 390º
C with a v holding time and bond force of 60 min and 1500 N, respectively. On the other hand, bonding on surfaces where 0.15&mu
m feedthrough lines exist can be done at 420º
C with a 100% yield using same holding time and bond force. Furthermore, glass frit bonding on glass wafers with lateral feedthroughs is performed at temperatures between 435-450º
C using different holding periods and bond forces. The yield is varied from %33 to %99.4 depending on the process parameters. The fabricated devices are wafer level vacuum packaged using the optimized glass frit and Au-Si eutectic bonding recipes. The performances of wafer level packages are evaluated using the integrated gyroscopes, resonators, and pirani vacuum gauges. Pressures ranging from 10 mTorr to 60 mTorr and 0.1 Torr to 0.7 Torr are observed in the glass frit packages, satisfying the requirements of various MEMS devices in the literature. It is also optically verified that Au-Si eutectic packages result in vacuum cavities, and further study is needed to quantify the vacuum level with vacuum sensors based on the resonating structures and pirani vacuum gauges.

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Cauthen, Stephen Michael. "Vacuum assisted resin transfer molding in the repair of reinforced concrete bridge structures." Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2008m/cauthen.pdf.

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Huan, Junjun. "Wafer-Level Vacuum-Encapsulated Ultra-Low Voltage Tuning Fork MEMS Resonator." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1493253273171541.

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Rujikiatkamjorn, Cholachat. "Analytical and numerical modelling of soft clay foundation improvement via prefabricated vertical drains and vacuum preloading /." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060523.123914/index.html.

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Ayoub, Mohammed. "Improvement of Cleanness in Melt of Tool Steel by Control of GasBubbles And Electromagnetic stirring in the ladle during vacuum treatment." Thesis, KTH, Tillämpad processmetallurgi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217287.

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Sahin, Emre. "Conceptual Design, Testing And Manufacturing Of An Industrial Type Electro-hydraulic Vacuum Sweeper." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613747/index.pdf.

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CONCEPTUAL DESIGN, TESTING AND MANUFACTURING OF AN INDUSTRIAL TYPE ELECTRO-HYDRAULIC VACUUM SWEEPER SAHIN, Emre M.Sc., Department of Mechanical Engineering Supervisor : Prof. Dr. Kahraman ALBAYRAK Co-Supervisor: Prof. Dr. Bilgin KAFTANOGLU September 2011, 156 pages In this thesis, conceptual design, testing, development and manufacturing processes of the cleaning (elevator and fan system) and electro-hydraulic systems of an industrial type vacuum sweeper are presented. Thesis is financially supported by Ministry of Science, Industry and Technology (Turkey) and Mü
san A.S. (Makina Ü
retim Sanayi ve Ticaret A.S.) under the SAN-TEZ projects with numbers 00028.STZ.2007-1 and 00623.STZ.2010-1. The main purpose is to make critical design changes on existing fan system, designing a new elevator system and eventually obtaining efficient and powerful cleaning system. For design, Catia and SolidWorks softwares are used. Within the SAN-TEZ project, all CFD solutions were provided by Punto Engineering. Unlike many industrial type vacuum sweepers, new design will be electrically and electro-hydraulic controlled. All cleaning system of new &lsquo
MÜ
SAN Vacuum Sweeper&rsquo
will be activated by using hydraulic motors (traction system including hydraulic system is driven by the brushless DC electric motor as well) and the power of all these systems is supplied by batteries which are placed in the middle of the vehicle. Elevator and fan system can be considered as a group for a street sweeper for cleaning operations. Fan and elevator systems both gain an important place especially in cleaning operations due to lifting heavy and small particles from the ground. Fan system is used for sucking the small materials and dust by vacuum and elevator system is used to elevate heavier materials such stones, bottles, cans. Therefore, it is essential to design an efficient and powerful fan and elevator system for a street sweeper. The thesis work includes the design, development, supervision of manufacturing, simulation and testing of the cleaning (elevator and fan systems) and electro-hydraulic system of the street cleaners.

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Franchini, Marco. ""Riorganizzazione dei flussi e della tracciabilità dei materiali in ottica di Lean Manufacturing: il caso di D.V.P. VACUUM TECHNOLOGY S.P.A."." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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L'elaborato di tesi riguarda la riorganizzazione dei flussi all'interno di un'azienda in provincia di Bologna: "D.V.P. VACUUM TECHNOLOGY S.P.A.". Dopo un'iniziale introduzione che mi ha visto partecipe a fianco dei lavoratori dei vari reparti, si sono riscontrate le inefficienze relative ai flussi produttivi. Sono state valutate preliminarmente alcune migliorie possibili riguardanti vari aspetti: un documento PPAP tra cliente e fornitore per rendere il flusso in ingresso più lineare, una gestione più efficace dei lotti logistici, una rivalorizzazione dei codici a “kanban” e l’implementazione di una logica “pull” tramite l’introduzione di pre-assemblati. Inoltre, confrontandosi con il Planning Manager, si è valutato prioritario studiare un sistema di tracciabilità adatto alla realtà produttiva oggetto di studio. Grazie alla disponibilità dei lavoratori e alla loro collaborazione si è riuscito a progettare uno strumento di facile utilizzo e di estrema utilità per conoscere in ogni momento dove si trova la merce. Si sono elaborati i passi necessari per preparare l’azienda a questo cambiamento rendendo partecipi i lavoratori e mostrando l’avanzamento del lavoro svolto. Alla fine di questo studio si sono valutati i costi per implementare la tracciabilità all’interno del software gestionale in uso e si sono presentati i benefici che il progetto avrebbe portato. L’analisi effettuata è risultata da stimolo per l’azienda che implementerà questo sistema all’interno di un software di schedulazione della produzione, la cui progettazione mi vedrà in prima persona coinvolto nel prossimo futuro.

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Albiz, Philippe, and Sara Glaerum. "The development of a vacuum cleaner concept adapted for storage through human-centred design." Thesis, KTH, Maskinkonstruktion (Inst.), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263842.

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Urbanisation and a growing population has created new demands for compact living and households. Household appliances perform an important role in modern homes, where the life-cycle of the products play a significant role. Products that spend most of their time in storage are required to answer new user demands to interplay and integrate into the household, including products such as vacuum cleaners. A master thesis project for KTH Industrial Design Engineering master track, carried out in collaboration with ESSIQ AB, investigated the user needs for vacuum cleaners in-uselifecycle. The research question was: How can a vacuum cleaner be designed and adapted to facilitate compact and easy storage for the user in a modern home, without compromising its current efficiency? The goal of the project was to design an innovative product concept through a human-centred design methodology. The methodology would lead to the creation of a product designed to fulfil the user needs by focusing on user experience. Knowledge about how vacuum cleaners are stored, used, interact and how it is interpreted in everyday life, were firstly found and then analysed. To develop a suitable concept proposal, needs and requirements were gathered through interviews and observations. New concept ideas were generated and evaluated through an iterative process resulting in the development of a final concept proposal. A proof-of-concept was developed to further support the final concept. The concept is a proposal for future development and introduces a new product category.
Urbanisering och en växande population ställer nya krav för kompakta och smarta ekosystem. Hemelektronik spelar en viktig roll i många moderna hem och är betydande för ett fungerande hushåll. Produkter som spenderar mesta av sin tid i förvaring erhåller således en essentiell funktion i ett ekosystem för individen, sådana produkter inkluderar dammsugare. Ett masterexamensarbete för den Kungliga Tekniska Högskolan, KTH, mastersprogram i Industridesign, utfördes tillsammans med ESSIQ AB för att undersöka de användarbehov som finns på dammsugare under sin livscykel. Problemformuleringen utgjordes av: Hur kan en dammsugare bli designad och anpassad för en användare, för att ge en kompakt och smidig förvaring i ett modernt hem, utan att kompromissa på sin nuvarande effektivitet? Målet för detta projekt var att designa ett innovativt koncept genom en användarfokuserad designmetod. En användarfokuserad process inkluderar en definition av användarens behov och fokuserar på att skapa en produkt utefter användarupplevelsen som svarar på de funna behoven. Hur dammsugaren förvaras, används, interagerar och hur den upplevs i det vardagliga livet, undersöktes för att kunna uppfylla målet. Ett anpassat konceptförslag var utvecklad genom identifiering av behov och problem hos användaren funna i intervjuer och tester. Idegenerering på nya konceptförslag utvecklades och utvärderades till ett slutgiltigt konceptförslag. Resultaten resulterade i ett konceptbevis, ett konceptförslag som uppfyller användarens behov. Konceptet fungerar som ett förslag och en grund för fortsatt arbete samt introducerar för en ny typ av produktkategori.

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McGivney, Eric. "Comparison of UV-C and Vacuum- UV induced AOT on the acute mortality of microalgae." Thesis, KTH, Mark- och vattenteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171839.

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Advanced oxidation technology (AOT) has been used to destroy microorganisms in ballast water by breaking down the cell membranes. The primary objective of this study was to determine the effects of a ballast water treatment system that uses a combination of UV-C (λ=254 nm), Vacuum-UV (VUV; λ=185 nm) and photocatalytic titanium dioxide (TiO2) on a freshwater algae, Pseudokirchneriella subcapitata, and a marine algae, Tetraselmis suecica. The coupling of a semiconductor, such as TiO2, with a UV source is known as an advanced oxidative technology (AOT). To test the effects of TiO2 and wave length on algae, dose-response experiments were conducted to determine the species median lethal dose (LC50) for each of the following treatments: UV-light emitted at 254 nm (UVλ=254 nm), UV-light emitted at 254 nm in the presence of TiO2 (AOTλ=254 nm), and UV-light emitted at λ=254 nm (90 %) and 185 nm (90 %) in the presence of TiO2 (AOTλ=185 + 254 nm). In both species, TiO2 significantly increased mortality, most likely due to the biologically harmful radicals generated at the TiO2 surface. The addition of the 185 nm wavelength significantly increased cell mortality in P. subcapitata, but not in T. suecica. Across all three treatments, P. subcapitata was more sensitive than T. suecica. The secondary purpose of this study was to assess the applicability of ImageJ, an image analysis software, for highthroughput data to analyze the effectiveness of ballast water treatment. ImageJ has been used to rapidly and accurately perform cell Live/Dead analysis; however, several hurdles were identified.

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Beh, Christopher Chun Keong. "Vacuum swing adsorption process for oxygen enrichment : a study into the dynamics, modelling and control." Monash University, Dept. of Chemical Engineering, 2003. http://arrow.monash.edu.au/hdl/1959.1/9533.

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Levin, Anders, and William Ellert. "Development of intelligent handle for assistance in vacuum extraction deliveries. : Optimization of low power designs with an experimental investigation of the battery recovery effect." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-262657.

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Karolinska Institutet has requested a new version of their measurement device in the form of an intelligent handle to be used in vacuum extraction deliveries at the hospital’s maternity ward. The development of the device has been focused on reducing size, manufacturability, energy optimization and to water proof the device. In the literature reviewing the energy optimization of portable devices, the disputed phenomenon of the battery recovery effect was identified as in interesting research area. The Battery Recovery Effect is based on the knowledge that chemical imbalances arises in certain battery types when subjected to load over longer periods. If the battery is allowed to rest, the chemical compounds are allowed to regain equilibrium increasing the efficiency of the chemical reactions. This implies that utilizing rest periods can increase the available energy of the battery. There are disagreements in academia regarding the existence of the battery recovery effect and few published investigations are based on proper measurements. Therefore this thesis verifies the experimental results by Arora et. al published in 2017 [1] regarding the existence of battery recovery effect. The investigation has been limited to Li-polymer and Ni-MH batteries. The batteries are drained with continuous and intermittent load profiles with varying sleep ratios, sleep periods and currents. The delivered charge and energy of the intermittent loads are compared to those for the continuous. For the specific batteries used in these tests and for the set of loads applied, no battery recovery effect could be identified. Instead a small decrease in both drained energy and delivered charge was observed when deploying intermittent loads. The new proposed handle design drastically reduce both size and weight. The handle is made water proof together with high robustness compared to the previous handle. Several assembly solutions where evaluated and the results indicate that epoxy glue were the best technique. For moving parts, silicone sealing ensures high water resistance while allowing necessary movement.
Karolinska Institutet är i behov av ett nytt elektroniskt mätverktyg i form av ett intelligent handtag som ska användas vid vakumförlossningar på sjukhusets förlossningsavdelning. I utvecklingen av mätverktyget ligger fokus på storleksminskning, förberedelse för serietillverkning, energioptimering och vattentätning. Under literaturstudien av energioptimering av batteridrivna enheter uppmärksammades det omtvistade fenomenet vid namn batteriåterhämtningseffekten. Ett fenomen som grundar sig i att ett batteri bygger upp kemiska obalanser när det utsatts för belastning under en längre period. Om batteriet tillåts vila får det en chans att återgå till sitt jämviktsläge vilket ökar verkningsgraden på de kemiska reaktionerna. Detta innebär att den tillgängliga energin i batteriet kan ökas om man tillåter batteriet att vila under vissa perioder. Eftersom batteriåterhämtningseffekten är omtvistad och få publiserade studier som undersöker fenomenet är baserade på experimentiella observationer, är det särskillt intressant med en verifiering av ett sådant resultat. Detta leder till att denna avhandling verifierar resultaten i artikeln publiserad av Arora m.fl. 2017 [1]. Detta med avgränsningen att endast undersöka Li-polymer och Ni-MH-batterier. Batterierna belastas med kontinuerlig och intermittent drift där vilotidskvoten, periodtiden och strömmen varieras. Den uttagna energin och laddningen jämförs sedan mellan de kontinuerliga och intermittenta drifterna. Med de batterier och strömprofiler som undersökts i denna studie sågs ingen ökning i vare sig laddning eller urladdad energi för de intermittenta lasterna. Istället gav de intermittenta lasterna en liten minskning i både urladdad energi och laddning. Vid utvecklingen av handtaget visar den nya designen att det går att göra handtaget både lättare och mindre. Handtaget blir också vattentätt och robustare än det tidigare handtaget. Flera monteringsalternativ har undersökts och lim bedöms vara den bästa lösningen. För rörliga delar rekommenderas silikon som montering och tätningslösning, detta ger hög vattentålighet samtidigt som den elastiska fogen tillåter nödvändig rörlighet.

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Bartrand, Timothy A. "Experimental investigation of a vacuum apparatus for zebra mussel control in closed conduits." Ohio : Ohio University, 1997. http://www.ohiolink.edu/etd/view.cgi?ohiou1177611369.

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35

Pan, Zhiwen [Verfasser], Antje [Gutachter] Kriltz, and Hartmut [Gutachter] Bartelt. "Consolidation of high melting SiO2-Al2O3-La2o3 glass powders with gas pressure vacuum viscous sintering technology / Zhiwen Pan ; Gutachter: Antje Kriltz, Hartmut Bartelt." Jena : Friedrich-Schiller-Universität Jena, 2016. http://d-nb.info/1177612178/34.

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36

Chen, Jihong. "Surface reactions of digermane, diethylgermane, triethylgermane, and deuterated ethylbromide on the GE(100) surface /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9737909.

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37

Morgan, Michael Ray. "Characterizing the Effects of Capillary Flow During Liquid Composite Molding." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5787.

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As the aerospace industry continues to incorporate composites into its aircraft, there will be a need for alternative solutions to the current autoclaving process. Liquid composite molding (LCM) has proven to be a promising alternative, producing parts at faster rates and reduced costs while retaining aerospace grade quality. The most important factor of LCM is controlling the resin flow throughout the fiber reinforcement during infusion, as incomplete filling of fibers is a major quality issue as it results in dry spots or voids. Void formation occurs at the resin flow front due to competition between viscous forces and capillary pressure. The purpose of this work is to characterize capillary pressure in vacuum infusion, and develop a model that can be incorporated into flow simulation. In all tests performed capillary pressure was always higher for the carbon fiber versus fiberglass samples. This is due to the increased fiber packing associated with the carbon fabric. As the fabric samples were compressed to achieve specific fiber volumes an increase in capillary pressure was observed due to the decrease in porosity. Measured values for capillary pressure in the carbon fabric were ~2 kPa, thus the relative effects of Pcap may become significant in flow modeling under certain slow flow conditions in composite processing.

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Porcelli, T. "'SPUTTER-ION PUMPS: PERFORMANCE-ASSESSMENT AND NOBLE-GAS PUMPING OPTIMISATION IN VIEW OF THE COMBINATION WITH NON-EVAPORABLE GETTERS'." Doctoral thesis, Università degli Studi di Milano, 2016. http://hdl.handle.net/2434/350260.

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The pumping properties of sputter-ion pumps (SIPs) have been studied in view of the combination with non-evaporable getters (NEG) for ultra-high vacuum applications. Several diode and noble-diode SIPs have been tested on a dedicated test bench and a specific procedure has been tuned, which allows to obtain reliable and reproducible values of pumping speed after saturation for different gases. In addition, several innovative combinations of cathode materials have been investigated, aiming in particular at an optimised pumping of noble gases and methane. These gas species cannot be pumped by NEG and thus their sorption represents the main task of a SIP in a combination pump. In parallel, each pair of cathodes has been analysed by FESEM/EDX and XRD, in order to find any possible correlation between their crystal structure, the surface modifications occurred during their functioning and the measured sorption performances.

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Clark, Kendal. "Ultra High Vacuum Low Temperature Scanning Tunneling Microscope for Single Atom Manipulation on Molecular Beam Epitaxy Grown Samples." Ohio University / OhioLINK, 2005. http://www.ohiolink.edu/etd/view.cgi?ohiou1125611713.

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40

Ghoreishi, Rima, and Fatmehsari Mehdi Ehsani. "Mechanical and Thermal Characterizations of Biobased Thermoset Resins from Soybean Oil Reinforced with Natural Fiber Using Vacuum Injection Moulding Technique." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20223.

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The aim of this research was to analyze the mechanical and thermal properties of composites andhybrid composites prepared with four types of jute fibers and two different resins; biobased thermosetresins acrylated epoxidized soybean oil (AESO) and mathacrylated anhydride modified soybean oil(MMSO). The processing technique used was vacuum injection molding (VIM). Tensile and, flexuraltestings and dynamic mechanical and thermal analysis (DMTA) were used to characterize thecomposites’ properties. The results showed that the AESO composites have better tensile and flexuralproperties. This may be due to the fact that the curing conditions were quite the same for both AESOand MMSO composites but MMSO composites showed different behavior during curing step. Theywere completely cured in a shorter time compared to AESO composites. Having equal curing time forboth resins’ composites can damage the structure of MMSO composites and hybrids. Tan delta peak forthe MMSO reinforced composites occurs at higher temperatures, compared to AESO reinforcedcomposites, which means better thermal properties for MMSO reinforced composites.

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Başaran, Ali Varol Remzi. "Toz metal parçalara ısıl ve mekanik yüzey işlemlerin birlikte uygulanabilirliğinin araştırılması /." Isparta : SDÜ Fen Bilimleri Enstitüsü, 2007. http://tez.sdu.edu.tr/Tezler/TF01086.pdf.

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42

Sadovský, Hynek. "Návrh uzlu křídlo-trup kompozitního letounu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232005.

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This master's thesis deals with design, strength calculation and technological solution of wing-fuselage joint for composite four-seater aeroplane certificated by CS-23. Design is focused on optimal space utilization, low weight and simple manufacturing and assembly. Main output is technical documentation consisting of drawings and technological lay-ups. Conceptual design was chosen after analysis and weight estimation. With strenght calculation for composite materials it was possible to design composition of primary parts and also specify manufacture processes. Assigment was solved by unusuall conceptual design, which claims higher precision manufacturing, but it saves weight.

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43

Eriksson, Alice. "Vatten- och kemikaliebesparande åtgärder samt reningstekniker inom ytbehandlingsindustrin : En studie av sköljvattenflödet på Calamo AB." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-73298.

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Denna studie har utförts på Calamo AB som arbetar med elektropolering och betning av rostfritt stål. Efter ytbehandlingssteget krävs sköljning av godset för att avlägsna kemikalierester vilket medför att stora mängder surt sköljvatten uppstår. Idag används våtkemisk fällningsanläggning för att rena sköljvattnet. Det befintliga reningsverket kräver flertalet tillsatser samtidigt som mängden slam som går till deponi är stor. Företaget vill utreda miljönyttan med att installera en vakuumindunstare för att ersätta det befintliga reningsverket som reningsmetod samt se över möjligheten att minska sin vattenförbrukning i samband med sköljning av gods för att bland annat kunna reducera storleken på indunstaren, minska belastningen på reningsstegen samt reducera mängden avfall. Studiens mål var att kartlägga uppkomsten av förorenat sköljvatten, identifiera potentiella vattenbesparande åtgärder och hur dessa åtgärder påverkar effektiviteten hos reningsanläggningarna. Samt visa hur installation av en vakuumindunstare förändrar företagets miljöpåverkan och utreda om det finns möjligheter att återanvända eller återvinna kemikalier och metaller från processen. Kartläggning och flödesmätningar av sköljvattenbehovet utfördes med hjälp av information av personal på Calamo samt en ultraljudsmätare. Vattenbesparande åtgärder, påverkan på reningsanläggning samt möjligheter till återvinning av kemikalier undersöktes genom litteraturstudie samt modellering i Excel. Utredningen av miljönyttan genom att ersätta befintligt reningsverk med vakuumindunstare utfördes med hjälp av LCA-värden hämtade från databasen SimaPro 8.0.4. Flera olika förslag på vattenbesparande åtgärder studerades och dessa gav en total vattenreduktion till reningsverket på mellan 5 - 81 % beroende på hur många samt vilka åtgärder som vidtogs. Enligt miljöberäkningarna genererar vakuumindunstaren 3 gånger högre utsläpp av koldioxidekvivalenter och 7 gånger större behov av icke förnyelsebar energi jämfört med det befintliga reningsverket. Genom att installera sprutskölj med motströmsteknik i stycke, sammankoppla befintliga sköljkar i avdelningarna betning, AVFKA samt automaten och installera sparsköljstank i alla avdelningar uppnås en reduktion av förorenat vatten till reningsstegen på 81%, vilket ytterligare kan optimeras genom installation av jonbytare, återanvändning av varmt vatten från renrum. Dessutom ökar föroreningshalten med 61% då dessa åtgärder vidtas vilket gynnar reningseffektiviteten i reningsanläggningarna och därav rekommenderas detta alternativ. Även kemikalieanvändningen och förluster av metalljoner reduceras avsevärt i processen genom användningen av sparskölj. Att installera vakuumindunstare rekommenderas inte på grund av dess stora energianvändning, dock kan andra resultat uppstå då andra LCA-värden används samt genom andra antaganden och hänsyn till kemikalie- och metallåtervinning istället för deponi.
This study has been carried out at Calamo AB, which works with electropolishing and pickling of stainless steel. After the surface treatment step, rinsing of the material is required to remove chemical residues, which results in large amounts of acid rinse water. Today, wet chemical precipitation plant is used to clean the rinse water. The existing treatment plant requires most additives, while the amount of sludge that goes to landfill is large. The company wants to investigate the environmental benefits of installing a vacuum evaporator to replace the existing sewage treatment plant as a purification method and to review the possibility of reducing its water consumption in connection with rinsing of goods in order to reduce the size of the evaporator, reduce the load on the purification steps and reduce the amount of waste. The aim of the study was to map the emergence of polluted rinse water, identify potential water-saving measures and how these measures affect the efficiency of the treatment plants. And show how the installation of a vacuum evaporator changes the company's environmental impact and investigate whether there are opportunities to reuse or recycle chemicals and metals from the process. Mapping and flow measurements of the rinse water requirement were performed using information from staff at Calamo and an ultrasonic meter. Water-saving measures, impact on treatment plant and opportunities for recycling of chemicals were investigated through literature study and modeling in Excel. The study of the environmental benefits by replacing existing treatment plants with vacuum evaporators was carried out using LCA values obtained from the database SimaPro 8.0.4. Several different proposals for water-saving measures were studied and these gave a total water reduction to the treatment plant of between 5 - 81% depending on how many and what measures were taken. According to the environmental calculations, the vacuum evaporator generates 3 times higher emissions of carbon dioxide equivalents and 7 times the need for non-renewable energy compared to the existing treatment plant. By installing spray rinse with countercurrent technology in one piece, interconnecting existing rinses in the cuttings departments, AVFKA as well as the dispenser and installing sparse rinse tank in all departments, a reduction of contaminated water to the purification steps of 81% is achieved, which can be further optimized by installation of ion exchangers, reuse of hot water from clean room. In addition, the pollutant content increases by 61% as these measures are taken, which favors the purification efficiency of the treatment plants and hence this option is recommended. The use of chemicals and losses of metal ions are also considerably reduced in the process through the use of savings rinses. Installing vacuum evaporators is not recommended due to its large energy use, however, other results may arise when other LCA values are used, as well as through other assumptions and considerations for chemical and metal recycling instead of landfill.

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Juan, Muñoz Jaime. "Development of the in situ forming of a liquid infused preform (ISFLIP) process : a new manufacturing technique for high performance fibre reinforced polymer (FRP) components." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/457775.

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A problem is not a problem anymore if no solution exists; therefore, in the present dissertation, a novel manufacturing technique, the In Situ Forming of a Liquid Infused Preform (ISFLIP), is proposed as a solution to some typical problems that manufacturing of Fibre Reinforced Polymer (FRP) parts through Vacuum Infusion (VI) involves, such as not taking advantage of the full potential of FRPs, long processing times and lack of reproducibility. ISFLIP is a hybrid process between VI and diaphragm forming in which a flat preform of a stack of reinforcement fabrics is firstly impregnated with a low viscosity matrix and, then, formed over a mould while the matrix is still in the low viscosity state. Being focused on high performance FRPs and shell components, from simple to complex double curvature shapes, a number of trade-offs between VI and diaphragm forming were overcome to lay the foundations from which ISFLIP ability to manufacture FRP components has been proven. In order to adopt a VI manufacturing methodology that fitted ISFLIP targets, important contributions to more general VI have also been made in terms of part quality optimization, addressing the major concern that void content is in VI, with competitive manufacturing times. An effective vacuum degassing procedure in which bubble formation is enhanced through high speed stirring, and a non-conventional filling and post-filling strategy are proposed for this purpose. Eventually, void content was virtually eliminated and post-filling time minimized without affecting fibre content. In ISFLIP, textile preforms are formed together with a series of auxiliary materials (plastic films and sheets, textile fabrics and knitted meshes), most of them showing different in-plane deformation mechanisms. Forming performance of preforms, as well as final part quality, are severely affected by interactions between all these materials different in nature. Uncertainties on this respect and an initial evaluation of attainable shapes were also addressed to define a more focused research plan to the final goal, still distant, of implementing ISFLIP in a real production environment. Results obtained throughout the research project give cause for reasonable optimism in ISFLIP potential and future prospects.
Un problema deja de ser un problema si no existe solución; por lo tanto, en esta disertación, una novedosa técnica de fabricación, el Conformado In Situ de una Preforma Infusionada con resina Líquida (ISFLIP, por sus siglas en inglés), se propone como solución a algunos problemas típicos relacionados con la fabricación de piezas de Polímero Reforzado con Fibra (FRP) a través de la Infusión por Vacío (VI), problemas tales como el desaprovechamiento de todo el potencial de los FRPs, largos tiempos de procesado y falta de reproducibilidad. ISFLIP es un proceso híbrido entre la VI y el conformado por membrana elástica en el que una preforma plana formada a partir de un apilado de tejidos de refuerzo es en primera instancia impregnada con una resina de baja viscosidad y, entonces, conformada sobre un molde mientras que la matriz permanece todavía en el estado de baja viscosidad. Estando centrado en los FRPs de altas prestaciones y en componentes con formas tipo concha, desde curvaturas simples hasta formas con doble curvatura complejas, un número importante de compensaciones entre la VI y el conformado por membrana se han ido superando para asentar las bases a partir de las cuales se ha probado la capacidad de ISFLIP para fabricas componentes de FRP. Con la vista puesta en implementar una metodología de fabricación por VI que cumpliese los objetivos definidos para ISFLIP, también se han realizado importantes contribuciones de carácter más general relacionadas con la VI en términos de optimización de parámetros de calidad de las piezas, abordando la gran preocupación que la porosidad final supone en la VI, y consiguiendo unos tiempos de fabricación competitivos. Con este propósito se han propuesto un proceso de desgasificación por vacío muy efectivo en el que se favorece la nucleación de burbujas mediante la agitación a alta velocidad, y una prometedora y no convencional estrategia de llenado y post-llenado de la preforma. Finalmente, se consiguió virtualmente eliminar la porosidad atrapada en las piezas, minimizando el tiempo de post-llenado sin afectar la fracción de fibra contenida. En ISFLIP las preformas textiles se conforman junto con una serie de materiales auxiliares (films y hojas plásticas, mallas y tejidos textiles), que muestran diferentes mecanismos de deformación en plano. El conformado de las preformas y el acabado final de las piezas se ve severamente afectado por todas las interacciones entre todos estos materiales diferentes en naturaleza. También se han abordado las incertidumbres que surgen al respecto y una evaluación inicial de las geometrías abarcables para definir un plan de investigación más concreto con el que poder afrontar la meta final, todavía distante, de implementar ISFLIP en un entorno productivo real. Los resultados obtenidos a lo largo de este proyecto de investigación permiten ser razonablemente optimistas en cuanto al potencial de ISFLIP y sus expectativas.

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Hueso, González Jaime. "Analysis of wedge-shaped waveguides and design of multipactor-resistant microwave bandpass filters. Análisis de guías de onda en forma de cuña y diseño de filtros de microondas paso-banda resistentes al efecto multipactor." Doctoral thesis, Editorial Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/33750.

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El efecto multipactor de ruptura en RF ha sido objeto de numerosos estudios desde hace más de 80 años, a partir del desarrollo de los primeros aceleradores de partículas en la primera mitad del siglo XX. A mediados de ese siglo, con el desarrollo de fuentes de alta potencia para aplicaciones radar y la llegada de los satélites artificiales, la investigación del multipactor cobró una considerable relevancia, al convertirse este fenómeno en un riesgo determinante para costosos proyectos comerciales. Las guías de onda con secciones rectas canónicas, como las rectangulares o las coaxiales, han sido tradicionalmente las más utilizadas en dispositivos de microondas. Sus principales ventajas son que sus campos electromagnéticos pueden resolverse analíticamente, lo que permite su aplicación directa en diseños complejos, y la simplicidad de su fabricación. Pero las capacidades de computación y las prestaciones de los algoritmos se han multiplicado con los años, lo que ha permitido ampliar el espectro de posibles topologías a geometrías casi arbitrarias, ofreciendo al diseñador una mayor libertad creativa. En todo caso, gran parte de los dispositivos de microondas actuales siguen confiando en la madurez y fiabilidad de las tecnologías de guía de onda tradicionales, que no requieren una inversión adicional en equipos de fabricación. La supresión del efecto multipactor es la motivación para arriesgarse a probar topologías de guía de onda innovadoras, como la guía en forma de cuña. Es en este contexto donde este trabajo de doctorado pretende ofrecer una contribuci'on. En primer lugar, se ha desarrollado un modelo numérico para predecir el efecto multipactor de ruptura en guías de onda huecas en forma de cuña. Esta herramienta ha permitido la identificación de criterios óptimos de diseño. Así mismo, se ha adaptado un método de síntesis de filtros paso-banda en guía rectangular para poder realizar un diseño similar pero basado en la nueva topología. Como culminación, las estructuras diseñadas se han fabricado y medido, con el fin de comprobar sus prestaciones electromagnéticas y su sensibilidad al efecto multipactor. Se ha registrado además una patente para proteger estos nuevos filtros. En resumen, el trabajo ha abarcado el ciclo de actividades relacionadas con el desarrollo industrial completo de un dispositivo pasivo de microondas: investigación básica, análisis, diseño, fabricación y calificación con medidas en el laboratorio. Estas medidas han comprobado la mejora prevista en los umbrales de multipactor de los filtros de microondas con topología en forma de cu¿na, y han confirmado que pueden ofrecer respuestas en frecuencia similares a aquellas de filtros basados en una guía de onda rectangular equivalente. Las implicaciones de los resultados han sido evaluadas a fondo y resumidas en este documento. Como observación final, se ha intentado redactar esta investigación de manera que refleje el proceso natural de aprendizaje, mostrando los aciertos y errores experimentados en el camino, todos los cuales han conducido al resultado final. Este reto no hubiera sido posible sin el apoyo y compromiso de varios profesionales de diferentes centros de investigación e industrias europeas (Universidad Politécnica de Valencia, Universidad de Valencia, Agencia Espacial Europea, Thales Alenia Espacio Espa¿na, Technische Universit¿at Darmstadt, 'Ecole Polythecnique F'ed'erale de Lausanne, Tesat, Aurora Software and Testing y Val Space Consortium), a los cuales estoy agradecido.
The multipactor RF breakdown effect has been object of numerous studies for over 80 years, since the development of the first particle accelerators in the beginning of the 20th century. Around the middle of that century, with the development of high power sources for radar applications and with the emergence of the artificial satellites, a new impulse was given to the multipactor research, since it became a risk for expensive commercial projects. Traditionally, waveguides with canonical cross sections, like rectangular or coaxial ones, have been the building blocks of most microwave devices. Their main advantages are that their electromagnetic fields can be solved analytically, enabling their direct application in complex designs, as well as their manufacturing simplicity. But over the years the computation capabilities and algorithms have continuously evolved, which has broadened the spectrum of possible topologies to almost arbitrary geometries, offering the designer more room for creativity. However, most of the current microwave devices still trust on the mature canonical waveguide technologies, which do not require an additional investment in manufacturing equipment. The suppression of the multipactor effect is the motivation for considering an innovative waveguide topology, like the wedge-shaped waveguide. It is within this context where this PhD work aims to offer a contribution. On the one hand, a numerical model for predicting the multipactor breakdown effect in wedge-shaped hollow waveguides has been developed. This tool has aided in the derivation of optimised design criteria. On the other hand, a bandpass filter synthesis method for rectangular waveguide has been adapted in order to calculate a similar design based on the new topology. As a culmination, the designed structures have been manufactured and tested, in order to verify their electromagnetic performance and their multipactor sensibility. A patent was also filed to protect these new filters. In short, this work has comprised the cycle of activities related to the whole industrial development of a passive microwave device: basic research, analysis, design, manufacturing and qualification through testing. These measurements have verified the predicted improvement in the multipactor thresholds of microwave filters with wedge-shaped topology, and have confirmed that they can offer similar frequency responses to the equivalent rectangular waveguide ones. The implications of the results have been thoroughly evaluated and summarised in this document. As a final remark, this research document has been drafted to reflect the natural learning process, and to show the rights and wrongs experienced in the way, which all have led to the final result. Such an endeavour would not have been possible without the support and commitment of several professionals from different European research centres and industries (Universidad Polit'ecnica de Valencia, Universidad de Valencia, European Space Agency, Thales Alenia Espacio Spain, Technische Universit¿at Darmstadt, 'Ecole Polythecnique F'ed'erale de Lausanne, Tesat, Aurora Software and Testing and Val Space Consortium), for which I am grateful.
Hueso González, J. (2013). Analysis of wedge-shaped waveguides and design of multipactor-resistant microwave bandpass filters. Análisis de guías de onda en forma de cuña y diseño de filtros de microondas paso-banda resistentes al efecto multipactor [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/33750
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Hedlöf, Ekvall Linnea. "Faktorer för effektiv infiltration av dagvatten hos permeabel asfalt." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-381159.

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För att permeabel asfalt skall vara ett bra sätt att ta hand om dagvatten i en stad med allt fler hårdgjorda ytor är det viktigt att den långsiktigt kan infiltrera dagvatten. Då det inte går att undvika att permeabel asfalt utsätts för små partiklar finns det en risk för att den skall sätta igen och förlora sin förmåga att infiltrera dagvatten. Som en skötselåtgärd för att förhindra att den sätter igen kan rengöring med högtryckstvätt och vakuumsugning göras. I detta examensarbete undersöktes det vilken effekt rengöring med högtryckstvätt och vakuumsugning har på permeabel asfalts infiltrationskapacitet. Vidare undersöktes även vilken typ av uppbyggnad av den permeabla asfalten som var mest lämplig för en effektiv infiltration. Litteraturstudie och intervjuer om permeabel asfalt samt infiltrationsförsök har utförts. För att uppbyggnaden av permeabel asfalt hydrologiskt sett skall fungera på ett bra sätt framkom det, i litteraturstudier och intervjuer, att det är viktigt att alla lager i uppbyggnaden verkligen är permeabla och att uppbyggnaden bör anpassas efter rådande förhållanden på anläggningsplatsen. Förhållanden som till exempel bör tas hänsyn till är underliggande jordart och närheten till grundvattenyta. I litteraturstudier och intervjuer framkom det att regelbunden skötsel av den permeabla asfalten är mycket viktig för dess långtidsfunktion att kunna infiltrera dagvatten. Infiltrationsförsöken skedde på två platser med permeabel asfalt i Uppsala; på en parkering vid ett köpcentrum i Gnista och på en lokalgata i Gränby backe. Infiltrationskapaciteten uppmättes innan och efter rengöring med högtryckstvätt och vakuumsugning på den permeabla asfalten. Vid Gnista kunde ingen infiltration uppmätas varken före eller efter rengöring. I Gränby backe ökade infiltrationskapaciteten från 0,47–0,71 mm/min till 1,24–12,23 mm/min efter rengöring. Denna infiltrationskapacitet visar på att den permeabla asfalten i Gränby backe kunde infiltrera dimensionerade regn med allt från 7 års återkomsttid till över 1000 års återkomsttid och med 10 minuters varaktighet. Det framkom i litteraturstudien att högtryckstvätt och vakuumsugning i olika studier har haft en positiv effekt på att upprätthålla och till viss del återskapa infiltrationskapaciteten hos permeabel asfalt. Vid infiltrationsförsöken i detta examensarbete påvisades även en positiv effekt, till viss del, av denna rengöringsmetod på infiltrationskapaciteten. Utifrån detta skulle rengöring med högtryckstvätt och vakuumsugning kunna rekommenderas som skötselmetod på permeabel asfalt. Resultaten i Gnista skiljde sig från de i Gränby backe då det i Gnista varken före eller efter rengöring fanns någon infiltrationskapacitet. Det skiljer sig endast ett år i ålder mellan de båda försöksplatserna, de har skötts på liknande sätt sedan anläggning och litteratur visar på att rengöring med högtryckstvätt och vakuumsugning skall ha en effekt på infiltrationskapaciteten. Detta kan tyda på att bristen på infiltrationsförmåga i Gnista kan bero på något annat än igensättning av den permeabla asfalten.
It is important that permeable asphalt is able to infiltrate storm water in the long-term for it to be a viable alternative for handling storm water. Permeable asphalt will always, in some way, be exposed to fine particles and therefore there is a risk that clogging will occur and that the permeable asphalt will lose its ability to infiltrate storm water. As a mean of maintenance cleaning with high pressure washing and vacuum cleaning can be done to prevent clogging. In this master thesis the effect of high pressure washing and vacuum cleaning on the infiltration capacity of permeable asphalt was examined. Also, the most suitable type of substructure for effective infiltration was examined. A literature study and interviews were conducted in combination with infiltration experiments on two locations with permeable asphalt in Uppsala. Literature studies and interviews state that for the substructure to be hydrologically well functioning it is important that every layer in the substructure really is permeable. The substructure should also be adapted to the conditions at the site where it is built. For example, conditions to take into consideration are soil type and highest level of groundwater. All through literature and interviews regular maintenance is said to be very important for the long-term functioning and infiltration of permeable asphalt. The infiltration experiments were conducted at a parking lot at a shopping center in Gnista and a small local street in Gränby backe. The infiltration capacity of the permeable asphalt was measured before and after maintenance with high pressure washing and vacuum suction. No infiltration capacity could be measured before or after maintenance at Gnista. In Gränby backe the infiltration capacity was 0,47-0,71 mm/min before maintenance and 1,24-12,23 mm/min after. According to this infiltration capacity the permeable asphalt in Gränby backe can infiltrate design rains with return periods of 7 years to over 1000 years and with a duration of 10 minutes. In research, high pressure washing, and vacuum suction were found to be able to maintain, and in some cases restore, infiltration capacity. In this master thesis’ infiltration experiments a positive effect on infiltration capacity by cleaning with high pressure washing and vacuum suction was partially found. According to this high pressure washing and vacuum suction can be recommended as a maintenance method on permeable pavement. The results from the two experiment sites stood apart from each other as Gnista had no infiltration capacity neither before nor after cleaning. In age, the two sites only differ by one year, and since they were built they have received similar maintenance and literature shows that high pressure washing and vacuums suction have an effect on infiltration capacity. This might indicate that the lack of infiltration capacity at Gnista might be due to something else than clogging.

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Seraphim, Rafael Molena. "Dessorção de gases de juntas soldadas em camaras de ultra-alto vacuo de aneis de armazanamento de eletrons." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263371.

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Orientadores: Antonio J. Ramirez, Maria Clara F. Ierardi
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-09T21:56:05Z (GMT). No. of bitstreams: 1 Seraphim_RafaelMolena_M.pdf: 6485115 bytes, checksum: 380cfffee5fa982ec74a9cdc78c88e3a (MD5) Previous issue date: 2007
Resumo: O avanço cientifico no estudo de átomos, moléculas e proteínas tem recebido uma contribuição significativa dos aceleradores de partículas, que em sua grande maioria são utilizados para a geração de radiação síncrotron. Por isso, o aprimoramento destas máquinas mostra-se de extrema importância para manter a ciência em seu contínuo avanço. O sistema de vácuo destas máquinas apresenta-se como um importante parâmetro para o seu bom funcionamento e melhorias neste promovem diretamente melhorias na qualidade da radiação síncrotron gerada. Logo, o desenvolvimento deste trabalho teve como principal objetivo o estudo das juntas soldadas das câmaras de vácuo que compõem o acelerador do Laboratório Nacional de Luz Síncrotron (LNLS). As juntas foram preparadas com o processo de soldagem GTAW (Gás Tungsten Arc Welding) mediante a utilização de diferentes gases de proteção, como Argônio, Hélio e Nitrogênio, e misturas entre estes. Os estudos concentraram-se na análise da influência dos gases de proteção na dessorção de gases das juntas soldadas. Para a caracterização destas utilizaram-se as técnicas de análise de superfícies Dessorção Estimulada por Elétrons (DEE) e Dessorção Estimulada por Fótons (DEF). Adicionalmente, realizou-se um estudo comparativo entre as duas técnicas buscando-se estabelecer relações entre os resultados fornecidos pelas mesmas. Os resultados mostraram que a dessorção de gases independe do gás de proteção de soldagem, mas depende sim do nível de oxidação das juntas soldadas, as quais podem apresentar altas taxas de dessorção caso estejam muito oxidadas e os óxidos não sejam camadas contínuas. Em conclusão pode-se dizer que as juntas soldadas para câmaras de vácuo de aceleradores de partículas devem apresentar baixos níveis de oxidação, e apesar das semelhanças encontradas entre a DEE e a DEF é aconselhável utilizar a DEF para a caracterização de superfícies para trabalharem com radiação síncrotron
Abstract: The scientific advance of atoms, molecules and proteins studies has received an important contribution from particle accelerators, which are mainly used to generate synchrotron radiation. Hence, the improvement of these machines is necessary to maintain the continuous advance of science. One of the key components for the adequate operation of these accelerators is the vacuum system. Thus, its improvement directly impacts on the quality of the generated synchrotron radiation. Therefore, the principal purpose of this work is to study the gas desorption from the welding joints on the particle accelerators vacuum chambers. The welds were prepared using the GTAW (Gas Tungsten Arc Welding) process with different shielding gases, as argon, helium and nitrogen, and some mixtures of them. The study concentrated on the analysis of the shielding gas influence on the gas desorption from the welded joints. The gas desorption of the joints was evaluated using Electron Stimulated Desorption (ESD) and Photon Stimulated Desorption (PSD). In addition, it was carried out a comparative study between both desorption techniques to establish relationships between the results provided by them. The results showed that the gas desorption from the welding joints does not depend on the welding shielding gas, but on the oxidation level of the joint, which can present high desorption yield if it is highly oxidized and these oxides are not a continuous film. Therefore, it is advisable to minimize the oxidation during welding of vacuum chambers for particle accelerators. Regarding the comparison between ESD and PSD they were found some similarities. However, PSD will have better performance characterizing surfaces that will be exposed to synchrotron radiation
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica

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Pivoda, Miroslav. "Návrh technologie výroby formy na odlévání dílu v malosériové výrobě." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229356.

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The aim of thesis is to describe the basic methods called Rapid Prototyping in theory and using one of them to create master model. Master model will be used to create silicone mould where a limited series of wax models will be by means of vacuum casting chamber. They will also be used to make ceramic form in which the final pad will be cast from freely accessible materials. After processing it the suitability of the proposed technologies for the production of the part in question will be assessed.

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Malkoc, Veysi. "Micropatterning Neuronal Networks on Nanofiber Platforms." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1367508074.

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Ponka, Ondřej. "Návrh výrobní technologie vakuové lisovací formy." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-382271.

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The master thesis deals with the design and production of the mold for vacuum forming. Specifically, how the existing and new mold materials affect their design and, consequently, their production technology. The thesis contains a brief description of the principle of vacuum molding. Technological and design principles of designing molds. Furthermore, the realization of the solution variants and the simulation of their production. The solved variants are subsequently evaluated from a technical and economic point of view.

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Dissertations / Theses on the topic 'Vacuum technology'

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